This invention is directed to a vent for a roof structure which allows for outgassing of the layers of material which comprise the roof. More specifically, this invention is directed to a one-way vent which allows for passage of gas from between the layers of the roof to the ambient but inhibits reverse flow of gas from the ambient to the layers.
In the construction of certain types of roofs a sub-floor is laid, and asphalt, or other similar material, laid over the sub-floor. Because of the nature of these roofs and the materials of which they are composed, certain gasses are created within the layers of the roofing material which, if unvented, will result in poor performance or breakdown of the roof itself.
Roofs of the type mentioned in the preceding paragraph are generally formed by overlaying a subflooring or the like with an asphalt material. The asphalt material tends to vent out certain gasses which are either trapped within the matrix of the asphalt or are formed from the asphalt itself subsequent to applying the same to the sub-flooring. If these gas bubbles are allowed to form, when subjected to expansion and contraction as the roof is exposed to heat and cold, the gas bubbles will deteriorate the roof because of flexure of the asphalt material as it responds to expansion and contraction of the gas bubble trapped inside.
In order to alleviate the problem of gas build-up within certain roofing structures, vents are utilized which tend to outgas the layers of the roof. Based on the requirements of building codes and the like, these vents are appropriately placed at a fixed distance from one another in order to facilitate the removal of gaseous products trapped within the layers of the roof.
Heretofore, these vents have been of a somewhat complicated nature and because of this, their use is not cost effective. The inclusion of these vents, however, is a necessity if proper performance of the roof is to be achieved. Additionally, while outgassing the roofs, the vents must also prevent reverse fluid flow, such that moisture, dirt and the like do not become trapped within the layers of the roof. The introduction of moisture between the layers of the roof can be highly detrimental in that once so introduced, the moisture tends to promote mold growth and the like which tends to deteriorate the structure of the roof.